Three vs 6 Cycles of Chemotherapy for High-Risk Retinoblastoma
Huijing Ye, Kang Xue, Ping Zhang, Rongxin Chen, Xiaowen Zhai, Li Ling, Wei Xiao, Lijuan Tang, Hongsheng Wang, Yuxiang Mao, Siming Ai, Yingwen Bi, Qing Liu, Yusha Zou, Jiang Qian, Huasheng Yang
Abstract
Importance: Adjuvant therapy is an important and effective treatment for retinoblastoma. However, there is a lack of head-to-head clinical trials comparing 3 vs 6 cycles of CEV chemotherapy (carboplatin, etoposide, and vincristine) for enucleated unilateral retinoblastoma with high-risk pathological features. Objective: To assess whether 3 cycles of CEV chemotherapy is noninferior to 6 cycles for enucleated unilateral retinoblastoma with high-risk pathological features. Design, Setting, and Participants: This double-center, randomized, open-label, noninferiority trial was conducted at 2 premier eye centers in China and included 187 patients who had undergone enucleation for unilateral retinoblastoma with high-risk pathological features (massive choroidal infiltration, retrolaminar optic nerve invasion, or scleral infiltration) between August 2013 and March 2024. The final date of follow-up was March 21, 2024. Interventions: Patients were randomly assigned to receive either 3 (n = 94) or 6 (n = 93) cycles of CEV chemotherapy regimen after enucleation. Main Outcomes and Measures: The primary end point was disease-free survival, with a noninferiority margin of 12%. Secondary end points encompassed overall survival, safety, economic burden, and the quality of life of children. Results: All 187 patients (median [IQR] age, 25.0 [20.0-37.0] months; 83 [44.4%] female) completed the trial. Median (IQR) follow-up was 79.0 (65.5-102.5) months. Five-year disease-free survival was 90.4% for the 3-cycle group vs 89.2% for the 6-cycle group (difference, 1.2% [95% CI, -7.5% to 9.8%]), which met the noninferiority criterion (P = .003 for noninferiority). The 6-cycle group experienced a higher frequency of adverse events, greater reduction in quality of life scores, and increased costs compared with the 3-cycle group. Conclusions and Relevance: Among patients with unilateral pathologic high-risk retinoblastoma, 3 cycles of CEV chemotherapy resulted in 5-year disease-free survival that was noninferior to 6 cycles of CEV chemotherapy. Trial Registration: ClinicalTrials.gov Identifier: NCT01906814.